Someone who is difficult to distinguish if they are a boy or a girl, so they are just a BOG, or Boggy.

Shitass Bankteller: Dude, is your cousin a boy or a girl?
One soon to be nicknamed Boggy: She's a girl, dude.
Shitass Bankteller: So she's a Boy Girl...a BOG...we should call you BOG...Boggy.
Boggy: Dam.